Nutrients

Mo Molybdenum

part of nitrate reductase; essential for N fixation

Chlorosis or twisting of leaves, whiptail disease in acidic soils.

Cu Copper

component of plastocyanin, aplastid pigment; present in lignin of xylem elements; activates enzymes

Young leaves dark green, twisted, and wilted; tips of roots and shoots remain alive; xylem loses rigidity; rarely deficient

Zn Zinc

ecessary for formation of pollen; involved in auxin synthesis; maintenance of ribosome structure; activates enzymes

Causes most problems in all micronutrients. Chlorosis, smaller leaves, thin; reduced internodes; distorted leaf margins; older leaves most affected.  New leaves grow contorted and twisted, dropping early.

Mn Manganese

photosynthetic O2 evolution; enzyme activator; electron transfers

Interveinal chlorosis; appears first on older leaves from base; necrosis common; disorganisation of lamellar membranes; immobile when pH over 7.5 and often accompanies Fe deficiency

B Boron

ssential for growth of pollen tubes; regulation of enzyme function; possible role in sugar transport

Death of apical meristem; leaves twisted and pale at base; swollen, discoloured root tips; young tissue most affected with grey specks, shoots turn grey

Fe Iron

equired for synthesis of chlorophyll; component of cytochromes and ferredoxin; cofactor of peroxidase and some other enzymes

Interveinal chlorosis; short and slender stems; buds remain alive; affects young leaves first, yellows from base, eventually necrosis; immobile when pH over 7.5 or high Cu levels

Cl Chlorine

activates photosynthetic elements; functions in water balance

Wilted leaves; chlorosis or bronzing; necrosis; stunted, thickened roots

Macronutrients

S Sulphur

part of coenzyme A and the amino acids and cystine and methionine; can be absorbed through stomata as gaseous SO2

Interveinal chlorosis; usually no necrosis; affects young leaves, lime green to yellow; stem elongation; rarely deficient; immobile when high pH or Ca levels

P Phosphorus

part of nucleic acids, sugar phosphates, and ATP; component of phospholipids of membranes; coenzymes

Stunted growth, dark blue/green to purple pigmentation; accumulation of anthocyanin pigments, delayed maturity; leaves contort and drop, often with dark blotches, lower leaf tips may turn brown and curl down; reddening on underside of stem; affects entire plant; low pH makes P unavailable as does cold, wet heavy soils; excess Fe and Zn in soil binds with phosphates; second to N, P is element most likely to be deficient

Mg Magnesium

part of chlorophyll; enzyme activator; protein synthesis

Interveinal chlorosis and reddening of leaves; red spots; leaf lips turn upward; older leaves most affected, and drop early; made unavailable by high K levels and low pH

Ca Calcium

membrane integrity; in middle lamella; functions as “second messenger”to co-ordinate plant's responses to many environmental stimuli; reversibly binds with calmodulin, which activates many enzymes

Required in large quantities. Death of root and shoot tips; very dark green foliage and slow growth; young leaves and shoots most affected, distorted and withered

K Potassium

regulates osmotic pressure of guard cells, thereby controlling opening and closing of stomata; activates more than 60 enzymes; necessary for starch formation

Chlorosis and necrosis, weak stems and roots; roots more susceptible to disease; young leaves develop mottling, older leaves most affected, first tips and margins; leaf tip curls (often downwards) and brown spots and tips develop; common in tomatoes, potatoes, beans and fruit.  Recovery is slow.

N Nitrogen

part of nucleic acids, chlorophyll, amino acids, protein, nucleotides, and co-enzymes

N is very mobile and dissipates quickly - element most likely to be deficient. General chlorosis, stunted growth; older leaves yellow first, stem(underside) and leaf veins might develop red/purplish colouration due to accumulation of anthocyanin pigments; small, brightly coloured fruit;

Toxicity shows as excessive lush, green foliage, stems weak, leaves go copper/brown and drop

O Oxygen

major component of plant's organic compounds

Rarely limiting enough to cause specific symptoms

C Carbon

major component of plant's organic compounds

Rarely limiting enough to cause specific symptoms

H Hydrogen

major component of plant's organic compounds

Rarely limiting enough to cause specific symptoms